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The objective of this research is to develop and characterize polyethylene composites with randomly and partially oriented hybrid filler (HF) based on multiwalled carbon nanotubes (MWCNTs) decorated with gamma iron (III) oxide (γ‐Fe2O3) nanoparticles (Fe2O3/MWCNTs). The structure of Fe2O3/MWCNTs hybrid is determined by X‐ray diffraction (XRD), Raman spectroscopy, and microscopy techniques (scanning electron microscopy–energy‐dispersive X‐ray spectroscopy, transmission electron microscopy). A low‐density polyethylene (LDPE) matrix is filled with 5 and 10 vol% HF. The effect of external magnetic field on the distribution of Fe2O3/MWCNTs in LDPE composites comparing to filler distribution without magnetic field is studied. The XRD and differential scanning calorimetry results confirm an increasing trend in the degree of crystallinity of LDPE matrix with increasing HF content and as an additional result of magnetic field application. The presence of more ordered Fe2O3/MWCNT particles in the matrix has enhanced the nucleation effect for LDPE crystallization process in composites under magnetic field. The effect of magnetic treatment on thermal, electrical, and thermoresistive properties of HF‐LDPE composites is studied. The highest thermoresistive response (723%) and fastest recovery are detected for the HF‐LDPE composite with 10 vol% magnetically oriented filler with the perspective to be applied as a critical temperature resistor. [ABSTRACT FROM AUTHOR]

This work describes impact of concentration of BiFeO3 submicrometric particles on piezoelectric performance and structural characteristics of 0–3 polymer composites with a polystyrene matrix. Bismuth ferrite particles are fabricated using reverse co‐precipitation method, followed by ultrasonic dispersion in a solvent to break up agglomerates formed during sintering, resulting in particles with a size of ≈200 nm. It is found that concentrations higher than 10 wt% BiFeO3 lead to a disturbance in natural organization of polystyrene. The hindered organization of side‐groups by submicrometric filler, occurring during solvent evaporation, strongly affects the mechanical properties of the finalcomposite, significantly increasing Young's modulus and tensile strength, but decreasing elongation. Such behavior is detected and described for the firsttime in literature. Piezoelectric examinations show that the thermal depolarization of nanogenerators has a different impact depending on the amountof piezoelectric phase. The study reveals that a voltage of over 4.8 V is generated when dynamic air pressure is applied at 11.54 bar for the composite containing only 2.5 wt% BiFeO3. For composites with 10% weight fraction or lower, decrease in generated voltage after thermal depolarization is about 24%, while for higher weight fractions (15 and 20 wt%) the decrease is around 35%. [ABSTRACT FROM AUTHOR]

The study investigated the microstructures, residual stress and mechanical properties of double carbides cermet coatings manufactured on AZ31 magnesium alloy substrate by high-velocity oxy-fuel spraying (HVOF). The HVOF spraying was carried out using a JP 5000 TAFA spray system and the commercially available powder WC-20Cr3C2-7Ni was used to manufacture coatings. The variable process parameter was spray distance (320, 360 and 400 mm). The top surfaces of the manufactured coatings are typical for HVOF coatings and is relatively smooth. Nevertheless, some irregularities and voids are observed. All coatings exhibit dense structure with relatively low porosity level (below 3 vol. %) as well as a robust mechanical binding to the substrate which indicates high adhesion. More deep microstructure analysis carried out by TEM microscopy revealed two types of precipitation: WC hexagonal phase in the space group P-6m2 with irregular shape and size as well as Cr7C3 orthorhombic one, in the space group P nma with a rounded shape and regular size. Phase composition after the spraying process indicates the hexagonal WC phase as the main one. Additionally, two chromium carbides phases, Cr3C2 and Cr3C7 have been identified. A small peak of hexagonal W2C carbide was found as well. Analysis of residual stress showed that both components of linear stress for all deposited coatings have a compressive nature. The increasing spray distance caused an increase of the linear stress values, from – 72.7 up to – 131.5 MPa for δ11 and from – 57.2 up to – 112.2 MPa for δ22. Such values could suggest that thermal stress generated during coating deposition was also low. In the case of the shear stress the values are much lower than linear one, but with the same tendency, increasing with longer spray distance: 14.2, 21.0 and 32.2 MPa for 320, 360 and 400 mm, respectively. The obtained results of HIT show a slight influence on the spray distance. With the increasing spraying distance, the value of hardness decreasing: 12.96, 12.53 and 11.76 GPa according to SD equal to 320, 360 and 400 mm, respectively. Similar was in the case of the EIT values: 315, 309 and 304 GPa for 320, 360 and 400 mm, respectively. All values of the fracture toughness were in the range between 3.5 and 4.0 MPa m1/2, with little influece of the spray distance. [ABSTRACT FROM AUTHOR]

The effect of particle size and oxidation degree of new carbon microfillers, based on coal pitch (CP) and petroleum pitch (PET) cokes, on the structure as well as thermal, mechanical, and electrical properties of the composites based on ultrahigh molecular weight polyethylene (UHMWPE) was investigated. The composites studied have a segregated structure of filler particle distribution in the UHMWPE matrix. It was found that composite with smaller CP grain fraction has the highest Young's modulus and electrical conductivity compared to the other composites studied, which can be the result of a large contribution of flake-shaped particles. Additionally, conductivity of this composite turned out to be similar to composites with well-known carbon nanofillers, such as graphene, carbon black, and CNTs. Additionally, the relationship between electrical conductivity and Young's modulus values of composites studied was revealed, which indicates that electrical conductivity is very sensitive to the structure of the filler phase in the polymer matrix. In general, it was established that the properties, especially the electrical conductivity, of the composites studied strongly depends on the size, shape, and oxidative treatment of CP and PET filler particles, and that the CP coke of appropriately small particle sizes and flake shape has significant potential as a conductive filler for polymer composites. [ABSTRACT FROM AUTHOR]

Growing demand for electric energy in newly developed electronic systems causes increasing interest in research on piezoelectric nanogenerators (PENGs). Design and fabrication of such devices is challenging, considering cost of materials used in their construction. This is the main reason why intensive research has begun on 0‐3 composites with piezoelectric properties. One of the most promising constituent materials for composites fabrication are polymers, due to their low cost and easy processing. Herein, we present fabricated wearable PENG with good impact and vibration energy conversion properties. Correlation between matrix stiffness and piezoelectric properties of 0‐3 type composite is proposed. It was found that composite with 10 wt.% of BiFeO3 particles exhibits power output density for vibrations, finger tapping, and air stream pressure P = 11.12 nW cm−3, P = 4.83 μW cm−3, and P = 769.2 μW cm−3, respectively. Decrease in stiffness of epoxy matrix results at least in two‐times lower power output density for this same PENG. The obtained results demonstrate that the fabricated BFO/epoxy composites show the wide applicability and potential to be integrated with other functional devices, for example, as a part of wearable devices in smart shoes. [ABSTRACT FROM AUTHOR]

Background: The year 2023 is a special time for Polish-Türkiye diplomatic relations. It is the 100th anniversary of the proclamation of the Republic of Türkiye and the 100th anniversary of its recognition by Poland. One area of this public and economic diplomacy is the debates on the different dimensions of the experiences, practices or frameworks of mutual cooperation between Poland and Türkiye, organised by the Foundation for Research on Türkiye in cooperation with the Regional Centre for International Debate in Krakow. The article is a synthesis of considerations undertaken in the area of Polish- Türkiye economic cooperation, with a particular focus on technology and innovation. Research objectives: The article aims to describe the potential pathways for enhancing mutual economic and political relations between Poland and Türkiye. Methods: The paper is based on content analysis of the debate on Polish-Türkiye cooperation in the area of innovation and technology, the potential of both countries in this respect, and the possibilities for its development. The debate took place in March 2023, and the authors were one of the panellists. The findings enrich statistical data coming from the Polish Central Statistical Office. Results: The paper highlights the strong economic ties between Poland and Türkiye, underscoring their joint endeavours across various industries. Both governments have ambitious plans to significantly boost their trade balance by 2023, with a particular emphasis on sectors like energy, mining, IT, automotive, and textiles, showcasing a mutual commitment to growth and partnership. Conclusions: Establishing and developing economic cooperation between Poland and Türkiye can benefit both countries. The mechanisms and initiatives mentioned above can help to increase trade and investment flows, create new business opportunities, and promote mutual learning and innovation. [ABSTRACT FROM AUTHOR]

This work presents the results of a tribological examination of polymer matrix composites reinforced with carbon foams with different porosity. The application of open-celled carbon foams allows an easy infiltration process by liquid epoxy resin. At the same time, carbon reinforcement remains its initial structure, which prevents its segregation in polymer matrix. Dry friction tests, conducted under 0.7, 2.1, 3.5 and 5.0 MPa loads, show that higher friction load results in higher mass loss, but it strongly lowers the coefficient of friction (COF). The change in coefficient of friction is related to the size of the pores of the carbon foam. Open-celled foams with pores size below 0.6 mm (40 and 60 ppi), used as a reinforcement in epoxy matrix, allow to obtain COF twice lower than composite reinforced with 20 ppi open-celled foam. This phenomenon occurs due to a change of friction mechanisms. In composites reinforced with open-celled foams, general wear mechanism is related to destruction of carbon components, which results in solid tribofilm formation. The application of novel reinforcement, in the form of open-celled foams with stable distance between carbon components, allows the decrease of COF and the improvement of stability, even under a very high friction load. [ABSTRACT FROM AUTHOR]

More than a year after the Russian aggression against Ukraine, a little can already be said about Turkey's attitude and the consequences of the conflict for Ankara. Turkey is balancing between Moscow and Kiev, trying to gain ground as a mediator, but also looking after its interests, especially economic ones. The text aims to analyse Turkish-Russian and Turkish-Ukrainian relations, especially since the outbreak of the war, and to answer the question of what the possible consequences of the Russian-Ukrainian war are for Turkey, whether it will be the big winner or rather the big loser of the situation. [ABSTRACT FROM AUTHOR]

Poles have found a place of refuge in Turkey (the Ottoman Empire) for centuries. For example, there is a village near Istanbul, Polonezköy (former Adampol), which was especially created with the Poles on the search for a second home in mind. When one considers the Polish community in Turkey during and after the Second World War, the contributions made by the Polish engineers to the development and expansion of the Turkish aviation and industry are often forgotten. The assistance that Turkey provided Poles with during the war as a 'friendly' neutral country has also been overlooked. Although, there were relatively few Poles living in Turkey during this period, they played a vital role in the development of the country. Nowadays they barely receive a mention. For the most part, their accomplishments have been overlooked. The aim of this paper is to draw attention to the shared past and to the period when these two countries came to each other's assistance once more. [ABSTRACT FROM AUTHOR]

In Turkey, during the Immediate Postwar Period (between 1945-1951), functioned the international specialization organizations, such as the United Nations Relief and Rehabilitation Administration (UNRRA), the Intergovernmental Committee on Refugees (IGCR) and the International Refugee Organization (IRO). Turkey was a country of minor importance in terms of the number of refugees in this period. According to data from IGCR, in 1946, there were 1221 registered refugees in Turkey. Among them were representatives of different nationalities, such as Poles, Yugoslavs, Albanians, Hungarians, Czechoslovaks, Austrians, Germans and Jews of various ethnicities. Later joined by Bulgarians and other anti-communist activists. The international specialization organizations faced various problems, from lack of money to the lack of cooperation from the Turkish government. IRO activists often complained about the sluggishness of Turkish officials. The problematic is important as an exemplification of the question of the protection of refugees by the International Community. [ABSTRACT FROM AUTHOR]

Over the centuries, the interest in languages of the Middle and Far East varied in dimensions. At the beginning, the oriental languages were taught at the Faculty of Theology, with the aim of improving the understanding of the Holy Bible. It was only in the 20th century that the role of the oriental studies began to be fully appreciated as a separate area of study, not affiliated with theology. A bit earlier, the so-called "Dragoman school" was founded, where the oriental languages were taught for diplomatic and translation needs. After the recovery of independence by Poland, the Chairs of Oriental Studies were founded in Cracow, Lviv and Warsaw. In this paper I present the development of oriental studies in Cracow and Lviv. I pay a particular attention to the relationship between those two universities and to people associated with both these academic centers. I compare the development of the Oriental Studies in Lviv and Cracow up to 1939 and emphasize the contribution of the orientalists from Lviv to the creation of the Oriental Studies in Cracow. [ABSTRACT FROM AUTHOR]